Related

New research on the finicky eating habits of children with autism finds that while autistic children tend to eat a less varied diet than other kids do, their dietary preferences have little negative effect on their height, weight and growth.

Researchers at the University of Bristol began with a database of children born from 1991 to 1992 who were enrolled in a long-term study in Avon, England. The children's caregivers completed detailed food questionnaires describing the kids' eating habits at five intervals, beginning at six months and continuing to age 4½. Since autism is generally not diagnosed until after age 2, when children begin speaking, the study captured the kids' eating habits well before parents were even aware their children could be afflicted with an autism spectrum disorder (ASD). That meant their answers to the questionnaires were unlikely to be biased by knowledge of eventual autism status. (See pictures of summer camp for autistic kids.)

By the end of the study, when the children were 7 years old, 79 had been diagnosed with an ASD; 12,901 had not. Researchers found that by the time they were 1 month old, the autistic children were already 35% more likely than unaffected children to be slow feeders. By their first birthday, their diets were considerably less varied  they ate fewer vegetables and fruits, but they also consumed fewer sweets and carbonated beverages. By that age, children with ASD were nearly twice as likely to be choosier about their food than unaffected children, according to their parents' reports. (See pictures of a journey into the world of autism.)

However, the scientists found no significant differences in the total energy intake or overall carbohydrate, fat and protein consumption between the autistic children and the controls at 18 months. All the children were similar in height, weight and body mass index (BMI; a ratio of height to weight used to measure obesity). "For parents of an autistic child, these data suggest they needn't be too concerned about their child's eating habits," says Pauline Emmett, a nutritionist and one of the authors of the research paper, which was published in Pediatrics. "In general, these children are not going to end up malnourished. I think it's a hopeful message for parents."

In addition, say experts, the new study suggests that feeding problems may be considered an early sign of autism. Most cases of ASD are diagnosed after age 2 or 3, when symptoms such as an inability to verbalize or a lack of development of language and social skills emerge. But Emmett and her team say changes in feeding patterns, which can materialize as early as several months after birth, could signal the presence of early autism. In some children with autism, dietary choosiness is related to physical symptoms of the disorder  for instance, if they are unable to chew or swallow properly, eating becomes a frustrating challenge. For other children, the issue is sensory, making certain textures and smells of food unpleasant; some children eat only crunchy foods, while others will stick to a white-foods-only diet. (See how autism numbers are rising.)

The authors do not suggest that feeding patterns are sufficient or necessary to diagnose autism, but they do think that dietary habits can be used in combination with other typical symptoms  like a child's inability to engage with his parents or siblings  to pick up the disorder. "It's an interesting idea to think of this as a red flag for screening for autism," says Geraldine Dawson, chief science officer for Autism Speaks. "So if a baby is showing persistent feeding problems, one of the things that should be considered should be autism."

Of course, there is a big difference between a finicky eater and a child with autism. Many toddlers are notoriously choosy about their foods and reticent to try new things. But persistent pickiness at mealtime could be a reason to look more carefully at a toddler's other behaviors, says Dr. Susan Hyman, a pediatrician at the University of Rochester Medical Center. "Food aversion may be part of a symptom complex that may be part of a bigger picture of behaviors," she says. "Beyond just feeding, for example, they may also be interested in fewer toys." (See six tips for traveling with an autistic child.)

Hyman is now conducting a more detailed study of the dietary habits of autistic children and is planning to take the British study one step further to understand the longer-term health effects of an unvaried diet in childhood on autistic adolescents and adults. Already there is evidence that children with autism tend to have thinner bones, and the current study confirms that kids with ASD consume slightly less vitamin D than nonautistic children. "Taking in adequate energy doesn't mean you are taking in adequate nutrients," says Hyman.

Still, Hyman says the current findings are valuable because they demonstrate that symptoms of autism may appear far earlier than previously thought. Early diagnosis means earlier interventions with treatments or behavior-modification programs that can help reduce the severity of the disorder. "There are treatment approaches to helping children who are picky eaters to learn to eat better," says Dawson. "We are still at the early stages of understanding the eating patterns that children with autism present with. It's an area in which we need a lot more research before we can fully understand it and best help these kids to be as healthy as possible."